In ETV6::RUNX1+ BCP-ALL, we identified a median of 18 SNVs/indels (range, 2–198) per case compared with 13.5 SNVs/indels (range, 5–35) per HD BCP-ALL case (ns, P = 0.057, Mann-Whitney test) (Suppl. The gene discussed is OPN1SW; the disease is acute lymphoblastic leukemia.